PESHAWAR, Pakistan -?A US drone strike killed seven people in Pakistan's volatile North Waziristan tribal region on Wednesday, security officials said, the first drone attack since a May 11 election in which the use of the unmanned aircraft was a major issue.

US President Barack Obama recently indicated he was scaling back the drone strike programme, winning cautious approval from Pakistan.

Pakistani security officials and tribesmen said the drone fired two missiles that struck a mud-built house at Chashma village, 3 km (2 miles) east of Miranshah, the administrative town of North Waziristan.

They said seven people were killed and four wounded. It was not immediately clear if the victims were the intended targets.

Prime Minister-elect Nawaz Sharif said this month that drone strikes were a "challenge" to Pakistan's sovereignty.

"We will sit with our American friends and talk to them about this issue," he said.

Obama's announcement of scaling back drone strikes was widely welcomed by the tribespeople of North Waziristan, where drones armed with missiles have carried out the most strikes against militants over the past seven years, sometimes with heavy civilian casualties.

Pakistan is a key ally in the US war on terror but, while combating militancy is still a high priority, polls show Americans' main concerns are the economy and other domestic issues such as healthcare.